Soil Variability Assessment for Sustainable Agriculture in Katsina State, Northwest, Nigeria
Soil assessment is a valuable first field-approach to determine the land suitability for agriculture production. Thus, a study was conducted to determine the variability of selected physio-chemical properties of soils under agriculture practice in Katsina State, Nigeria. The agriculture area was divided into land units and a total of 5 soil profile pits were excavated corresponding to each unit. The different soil horizon in soil profile were described using soil taxonomy, with 500g of sample were collected from each soil horizon. A total of fifteen (15) samples were collected from the profile pits (three in each pit from three different horizons). GIS (Geographical Information System) techniques were integrated to the soil data from the laboratory soil analyses. Following that, ArcGIS 10.3 used to generate the physio-chemical characteristic thematic maps of the selected soil characteristic parameters. Climate condition; rainfall and temperature, plus physical properties; bulk density (BD), drainage, erosion, soil depth (SD), slope, water holding capacity, and chemical properties; organic carbon (OC), cation exchangeable capacity (CEC) and soil pH were determined and analyzed. The rainfall trend of the area increases at decreasing with the highest peak at 2017. All the land units were characterized with the required soil pH as ranged between (6.0-6.76). The highest CEC value was found in land unit 5 (9.02cmol/kg) with lowest in land unit 4 (4.03cmol/kg). The correlation analysis of soil properties of all the five land units was computed in (table 7). This shows that the parameters of the land units are not independent. The indications in this results is that some soil parameters of the land units are significantly correlated. The analysis reveals that there is a significant relationship among the land units in study area on OC, AWC and erosion activities while in terms of CEC, PH and soil depth there is no significant differences at p value of 0.05. As such knowledge on climate and physio-chemical properties of soil are very essential so as to help farmers and others land users in Katsina, North West zone to identify areas that are best for agricultural land uses.